China National Space Administration said Tianwen-2 completed about a 400‑day, ~1
bln km approach and has rendezvoused with asteroid 2016 HO3, arriving at roughly
20 km and beginning scientific observations. The probe captured imagery during
approach, and teams used the optical-navigation data to refine the asteroid’s
ephemeris, cutting position error from hundreds of km to the km scale. Tianwen-2
was launched from Xichang Satellite Launch Center on May 29, 2025.
